systemctl — Control the systemd system and service manager
systemctl [OPTIONS...]  {COMMAND}  [NAME...] 
systemctl may be used to introspect and control the state of the systemd(1) system and service manager.
The following options are understood:
--help, -hPrints a short help text and exits.
--versionPrints a short version string and exits.
--type=, -tWhen listing units,
                                limit display to certain unit
                                types. If not specified units of all
                                types will be shown. The argument
                                should be a unit type name such as
                                service,
                                socket and
                                similar.
--property=, -pWhen showing
                                unit/job/manager properties, limit
                                display to certain properties as
                                specified as argument. If not
                                specified all set properties are
                                shown. The argument should be a
                                property name, such as
                                MainPID. If
                                specified more than once all
                                properties with the specified names
                                are shown.
--all, -aWhen listing units, show all units, regardless of their state, including inactive units. When showing unit/job/manager properties, show all properties regardless whether they are set or not.
--failedWhen listing units,
                                show only failed units. Do not confuse
                                with
                                --fail.
--fullDo not ellipsize unit names and truncate unit descriptions in the output of list-units and list-jobs.
--failIf the requested
                                operation conflicts with a pending
                                unfinished job, fail the command. If
                                this is not specified the requested
                                operation will replace the pending job,
                                if necessary. Do not confuse
                                with
                                --failed.
--ignore-dependenciesWhen enqueuing a new job ignore all its dependencies and execute it immediately. If passed no required units of the unit passed will be pulled in, and no ordering dependencies will be honoured. This is mostly a debugging and rescue tool for the administrator and should not be used by applications.
--quiet, -qSuppress output to STDOUT in snapshot, is-active, enable and disable.
--no-blockDo not synchronously wait for the requested operation to finish. If this is not specified the job will be verified, enqueued and systemctl will wait until it is completed. By passing this argument it is only verified and enqueued.
--no-legendDo not print a legend, i.e. the column headers and the footer with hints.
--no-pagerDo not pipe output into a pager.
--systemTalk to the systemd system manager. (Default)
--userTalk to the systemd manager of the calling user.
--order, --requireWhen used in
                                conjunction with the
                                dot command (see
                                below), selects which dependencies are
                                shown in the dependency graph. If
                                --order is passed
                                only dependencies of type
                                After= or
                                Before= are
                                shown. If --require
                                is passed only dependencies of type
                                Requires=,
                                RequiresOverridable=,
                                Requisite=,
                                RequisiteOverridable=,
                                Wants= and
                                Conflicts= are
                                shown. If neither is passed, shows
                                dependencies of all these
                                types.
--no-wallDon't send wall message before halt, power-off, reboot.
--globalWhen used with enable and disable, operate on the global user configuration directory, thus enabling or disabling a unit file globally for all future logins of all users.
--no-reloadWhen used with enable and disable, do not implicitly reload daemon configuration after executing the changes.
--no-ask-passwordWhen used with start and related commands, disables asking for passwords. Background services may require input of a password or passphrase string, for example to unlock system hard disks or cryptographic certificates. Unless this option is specified and the command is invoked from a terminal systemctl will query the user on the terminal for the necessary secrets. Use this option to switch this behavior off. In this case the password must be supplied by some other means (for example graphical password agents) or the service might fail.
--kill-who=When used with
                                kill, choose which
                                processes to kill. Must be one of
                                main,
                                control or
                                all to select whether
                                to kill only the main process of the
                                unit, the control process or all
                                processes of the unit. If omitted
                                defaults to
                                all.
--signal=, -sWhen used with
                                kill, choose which
                                signal to send to selected
                                processes. Must be one of the well
                                known signal specifiers such as
                                SIGTERM, SIGINT or SIGSTOP. If
                                omitted defaults to
                                SIGTERM.
--force, -fWhen used with enable, override any existing conflicting symlinks.
When used with
                                halt,
                                poweroff,
                                reboot or
                                kexec execute the
                                selected operation without shutting
                                down all units. However, all processes
                                will be killed forcibly and all file
                                systems are unmounted or remounted
                                read-only. This is hence a drastic but
                                relatively safe option to request an
                                immediate reboot. If
                                --force is specified
                                twice for these operations, they will
                                be executed immediately without
                                terminating any processes or umounting
                                any file systems. Warning: specifying
                                --force twice with
                                any of these operations might result
                                in data loss.
--root=When used with enable/disable/is-enabled (and related commands), use alternative root path when looking for unit files.
--runtimeWhen used with
                                enable/disable/is-enabled (and related commands), make
                                changes only temporarily, so that they
                                are dropped on the next reboot. This
                                will have the effect that changes are
                                not made in subdirectories of
                                /etc but in
                                /run, with
                                identical immediate effects, however,
                                since the latter is lost on reboot,
                                the changes are lost
                                too.
-H, --hostExecute operation remotely. Specify a hostname, or username and hostname separated by @, to connect to. This will use SSH to talk to the remote systemd instance.
-P, --privilegedAcquire privileges via PolicyKit before executing the operation.
--lines=, -nWhen used with status controls the number of journal lines to show, counting from the most recent ones. Takes a positive integer argument. Defaults to 10.
--follow, -fWhen used with status continously prints new journal entries as they are appended to the journal.
--output=, -oWhen used with
                                status controls the
                                formatting of the journal entries that
                                are shown. For the available choices
                                see
                                systemd-journalctl(1). Defaults
                                to
                                short.
The following commands are understood:
List known units.
Start (activate) one or more units specified on the command line.
Stop (deactivate) one or more units specified on the command line.
Asks all units listed
                                on the command line to reload their
                                configuration. Note that this will
                                reload the service-specific
                                configuration, not the unit
                                configuration file of systemd. If you
                                want systemd to reload the
                                configuration file of a unit use the
                                daemon-reload
                                command. In other words: for the
                                example case of Apache, this will
                                reload Apache's
                                httpd.conf in the
                                web server, not the
                                apache.service
                                systemd unit file. 
This command should not be confused with the daemon-reload or load commands.
Restart one or more units specified on the command line. If the units are not running yet they will be started.
Restart one or more units specified on the command line if the units are running. Do nothing if units are not running. Note that for compatibility with Red Hat init scripts condrestart is equivalent to this command.
Reload one or more units if they support it. If not, restart them instead. If the units are not running yet they will be started.
Reload one or more units if they support it. If not, restart them instead. Do nothing if the units are not running. Note that for compatibility with SysV init scripts force-reload is equivalent to this command.
Start the unit specified on the command line and its dependencies and stop all others.
This is similar to changing the runlevel in a traditional init system. The isolate command will immediately stop processes that are not enabled in the new unit, possibly including the graphical environment or terminal you are currently using.
Note that this works only on units
                                where AllowIsolate= is
                                enabled. See
                                systemd.unit(5)
                                for details.
Send a signal to one
                                or more processes of the unit. Use
                                --kill-who= to select
                                which process to kill. Use
                                --kill-mode= to
                                select the kill mode and
                                --signal= to select
                                the signal to send.
Check whether any of
                                the specified units are active
                                (i.e. running). Returns an exit code
                                0 if at least one is active, non-zero
                                otherwise. Unless
                                --quiet is specified
                                this will also print the current unit
                                state to STDOUT.
Show terse runtime status information about one or more units, followed by its most recent log data from the journal. This function is intended to generate human-readable output. If you are looking for computer-parsable output, use show instead. If a PID is passed information about the unit the process of the PID belongs to is shown.
Show properties of one
                                or more units, jobs or the manager
                                itself. If no argument is specified
                                properties of the manager will be
                                shown. If a unit name is specified
                                properties of the unit is shown, and
                                if a job id is specified properties of
                                the job is shown. By default, empty
                                properties are suppressed. Use
                                --all to show those
                                too. To select specific properties to
                                show use
                                --property=. This
                                command is intended to be used
                                whenever computer-parsable output is
                                required. Use
                                status if you are
                                looking for formatted human-readable
                                output.
Reset the
                                'failed' state of the
                                specified units, or if no unit name is
                                passed of all units. When a unit fails
                                in some way (i.e. process exiting with
                                non-zero error code, terminating
                                abnormally or timing out) it will
                                automatically enter the
                                'failed' state and
                                its exit code and status is recorded
                                for introspection by the administrator
                                until the service is restarted or
                                reset with this
                                command.
List installed unit files.
Enable one or more
                                unit files, as specified on the
                                command line. This will create a
                                number of symlinks as encoded in the
                                [Install] sections
                                of the unit files. After the symlinks
                                have been created the systemd
                                configuration is reloaded (in a way
                                that is equivalent to
                                daemon-reload) to
                                ensure the changes are taken into
                                account immediately. Note that this
                                does not have the effect that any of
                                the units enabled are also started at
                                the same time. If this is desired a
                                separate start
                                command must be invoked for the
                                unit.
This command will
                                print the actions executed. This
                                output may be suppressed by passing
                                --quiet.
Note that this operation creates only the suggested symlinks for the units. While this command is the recommended way to manipulate the unit configuration directory, the administrator is free to make additional changes manually, by placing or removing symlinks in the directory. This is particularly useful to create configurations that deviate from the suggested default installation. In this case the administrator must make sure to invoke daemon-reload manually as necessary, to ensure his changes are taken into account.
Enabling units should not be confused with starting (activating) units, as done by the start command. Enabling and starting units is orthogonal: units may be enabled without being started and started without being enabled. Enabling simply hooks the unit into various suggested places (for example, so that the unit is automatically started on boot or when a particular kind of hardware is plugged in). Starting actually spawns the daemon process (in case of service units), or binds the socket (in case of socket units), and so on.
Depending on whether
                                --system,
                                --user or
                                --global is specified
                                this enables the unit for the system,
                                for the calling user only
                                or for all future logins of all
                                users. Note that in the latter case no
                                systemd daemon configuration is
                                reloaded.
Disables one or more units. This removes all symlinks to the specified unit files from the unit configuration directory, and hence undoes the changes made by enable. Note however that this removes all symlinks to the unit files (i.e. including manual additions), not just those actually created by enable. This call implicitly reloads the systemd daemon configuration after completing the disabling of the units. Note that this command does not implicitly stop the units that is being disabled. If this is desired an additional stopcommand should be executed afterwards.
This command will print the
                                actions executed. This output may be
                                suppressed by passing
                                --quiet.
Checks whether any of
                                the specified unit files is enabled
                                (as with
                                enable). Returns an
                                exit code of 0 if at least one is
                                enabled, non-zero otherwise. Prints
                                the current enable status. To suppress
                                this output use
                                --quiet.
Reenable one or more
                                unit files, as specified on the
                                command line. This is a combination of
                                disable and
                                enable and is
                                useful to reset the symlinks a unit is
                                enabled with to the defaults
                                configured in the
                                [Install] section
                                of the unit file.
Reset one or more unit files, as specified on the command line, to the defaults configured in a preset file. This has the same effect as disable or enable, depending how the unit is listed in the preset files.
Mask one or more unit
                                files, as specified on the command
                                line. This will link these units to
                                /dev/null, making
                                it impossible to start them. This is a stronger version
                                of disable, since
                                it prohibits all kinds of activation
                                of the unit, including manual
                                activation. Use this option with
                                care.
Unmask one or more unit files, as specified on the command line. This will undo the effect of mask.
Link a unit file that is not in the unit file search paths into the unit file search path. This requires an absolute path to a unit file. The effect of this can be undone with disable. The effect of this command is that a unit file is available for start and other commands although it isn't installed directly in the unit search path.
Load one or more units specified on the command line. This will simply load their configuration from disk, but not start them. To start them you need to use the start command which will implicitly load a unit that has not been loaded yet. Note that systemd garbage collects loaded units that are not active or referenced by an active unit. This means that units loaded this way will usually not stay loaded for long. Also note that this command cannot be used to reload unit configuration. Use the daemon-reload command for that. All in all, this command is of little use except for debugging.
This command should not be confused with the daemon-reload or reload commands.
List jobs that are in progress.
Cancel one or more jobs specified on the command line by their numeric job IDs. If no job id is specified, cancel all pending jobs.
Dump server status. This will output a (usually very long) human readable manager status dump. Its format is subject to change without notice and should not be parsed by applications.
Generate textual
                                dependency graph description in dot
                                format for further processing with the
                                GraphViz
                                dot(1)
                                tool. Use a command line like
                                systemctl dot | dot -Tsvg >
                                systemd.svg to generate a
                                graphical dependency tree. Unless
                                --order or
                                --require is passed
                                the generated graph will show both
                                ordering and requirement
                                dependencies.
Create a snapshot. If
                                a snapshot name is specified, the new
                                snapshot will be named after it. If
                                none is specified an automatic
                                snapshot name is generated. In either
                                case, the snapshot name used is
                                printed to STDOUT, unless
                                --quiet is
                                specified.
A snapshot refers to a saved state of the systemd manager. It is implemented itself as a unit that is generated dynamically with this command and has dependencies on all units active at the time. At a later time the user may return to this state by using the isolate command on the snapshot unit.
Remove a snapshot previously created with snapshot.
Reload systemd manager configuration. This will reload all unit files and recreate the entire dependency tree. While the daemon is reloaded, all sockets systemd listens on on behalf of user configuration will stay accessible.
This command should not be confused with the load or reload commands.
Reexecute the systemd manager. This will serialize the manager state, reexecute the process and deserialize the state again. This command is of little use except for debugging and package upgrades. Sometimes it might be helpful as a heavy-weight daemon-reload. While the daemon is reexecuted all sockets systemd listens on on behalf of user configuration will stay accessible.
Dump the systemd manager environment block. The environment block will be dumped in straight-forward form suitable for sourcing into a shell script. This environment block will be passed to all processes the manager spawns.
Set one or more systemd manager environment variables, as specified on the command line.
Unset one or more systemd manager environment variables. If only a variable name is specified it will be removed regardless of its value. If a variable and a value are specified the variable is only removed if it has the specified value.
Enter default mode. This is mostly equivalent to start default.target.
Enter rescue mode. This is mostly equivalent to isolate rescue.target but also prints a wall message to all users.
Enter emergency mode. This is mostly equivalent to isolate emergency.target but also prints a wall message to all users.
Shut down and halt the
                                system. This is mostly equivalent to
                                start halt.target
                                but also prints a wall message to all
                                users.  If combined with
                                --force shutdown of
                                all running services is skipped,
                                however all processes are killed and
                                all file systems are unmounted or
                                mounted read-only, immediately
                                followed by the system halt.  If
                                --force is specified
                                twice the the operation is immediately
                                executed without terminating any
                                processes or unmounting any file
                                systems. This may result in data
                                loss.
Shut down and
                                power-off the system. This is mostly
                                equivalent to start
                                poweroff.target but also
                                prints a wall message to all users. If
                                combined with --force
                                shutdown of all running services is
                                skipped, however all processes are
                                killed and all file systems are
                                unmounted or mounted read-only,
                                immediately followed by the powering
                                off. If --force is
                                specified twice the the operation is
                                immediately executed without
                                terminating any processes or
                                unmounting any file systems. This may
                                result in data loss.
Shut down and reboot
                                the system. This is mostly equivalent
                                to start
                                reboot.target but also
                                prints a wall message to all users. If
                                combined with --force
                                shutdown of all running services is
                                skipped, however all processes are
                                killed and all file systems are
                                unmounted or mounted read-only,
                                immediately followed by the reboot. If
                                --force is specified
                                twice the the operation is immediately
                                executed without terminating any
                                processes or unmounting any file
                                systems. This may result in data
                                loss.
Shut down and reboot
                                the system via kexec. This is mostly
                                equivalent to start
                                kexec.target but also prints
                                a wall message to all users. If
                                combined with --force
                                shutdown of all running services is
                                skipped, however all processes are killed
                                and all file systems are unmounted or
                                mounted read-only, immediately
                                followed by the
                                reboot.
Ask the systemd
                                manager to quit. This is only
                                supported for user service managers
                                (i.e. in conjunction with the
                                --user option) and
                                will fail otherwise.